Methods for oligomerization of ethylene and other alpha olefins are widely known. Such oligomerization methods include oligomerizing the monomer (e.g., ethylene) in a reactor in the presence of catalyst, co-catalyst and solvent. Following oligomerization in the reaction, product material comprising oligomer and/or polymer, non-reacted monomer(s), catalyst, co-catalyst and solvent can be discharged from the reactor and can be further processed. Suitable further processing can include catalyst deactivation, separation of solvent and oligomer product, and oligomer fractionation. The oligomerization methods can be operated continuously such that unreacted monomer or solvent can be recirculated in the oligomerization plant.
At times, the oligomerization reactors and other plant equipment, in particular reactor piping, require cleaning, as fouling or plugging can occur at the walls of the piping. One method to clean the reactor piping has been to flush the piping with a flushing medium, preferably at an elevated temperature. This process, however, can be undesirable because flushing the piping and reactor equipment generally produces significant quantities of contaminated flushing medium to be disposed of. Disposing of the contaminated flushing medium is often difficult and cost-intensive.
Accordingly, there is a continuing need for a process for processing an oligomerization product stream such that fouling or plugging of reactor piping is reduced or eliminated. It would be particularly advantageous to avoid the need for use of costly imported flushing medium that requires the installation of additional processing equipment and disposal through difficult and cost-intensive means.